The present invention relates to a technology of calculating and displaying a placed-order amount and an inventory amount which vary depending on timing of modifying a sales plan or lead time, to thereby support evaluations of the sales plan.
Material Requirements Planning (MRP) is a technique of material planning, which was proposed in the 1970s in the United States and has gained a broader range of application in recent years. The MRP method is intended to obtain, with respect to required items for a product, such as assemblies, components, and raw materials, a plan for purchasing or manufacturing necessary items in required quantities by a required deadline, based on a production plan or a sales plan prepared at product level, a bill of material, and information on inventory and placed-orders (remaining orders) or the like.
Further, as a method of accurately estimating future inventory assets even in a case where estimated volume of sales of a product in reality is inconsistent with its sales plan, a simulation system is proposed for calculating an inventory assets balance, in which a time point, based on which MRP calculation is performed, is moved forward, and MRP calculation is performed at each advanced time point to obtain an inventory quantity based on an incoming quantity/outgoing quantity and an inventory quantity at a previous time point, to thereby calculate how the inventory changes at each time point (refer to Japanese Patent Laid-open No. 2004-161437).
According to the conventional technology, it is possible to calculate how a future inventory assets balance changes, based on a current sales plan; however, it is difficult to see how the inventory assets balance changes, depending on the timing of revising the sales plan.
Also, according to the conventional system, it is possible to understand the behavior of components which eventually arrive in stock to increase the inventory; however, it is difficult to find out when the order for the components being in stock was placed and at what timing the components are purchased in a large quantity under the current plan. Accordingly, it is not possible to conduct a quantitative discussion on decision making timing, that is, how soon a corporate manager has to make a decision to change the plan in order to prevent increased risk of deteriorating business performance.